Debt Service Ratios – GDS and TDS Combined
Understand GDS and TDS debt service ratios in Canadian real estate, how they impact mortgage approval, and how to stay within limits to qualify.
May 22, 2025
What are Debt Service Ratios?
Debt service ratios, including Gross Debt Service (GDS) and Total Debt Service (TDS), are financial metrics used by lenders to assess a borrower's ability to manage housing costs and overall debt.
Why Debt Service Ratios Matter in Real Estate
In Canadian real estate, GDS and TDS ratios help lenders evaluate mortgage affordability.
- GDS measures housing-related expenses (mortgage, property taxes, heating, and 50% of condo fees) as a percentage of gross income. The maximum allowable GDS is typically 32%.
- TDS includes all debt payments (housing expenses plus loans, credit cards, etc.). The TDS threshold is generally 40–44%.
Lenders calculate these ratios during the mortgage approval process. Staying within the approved limits ensures borrowers can manage their monthly obligations without financial strain.
For example, if your gross monthly income is $6,000, your GDS should not exceed $1,920, and your TDS should stay below $2,640–$2,800.
High GDS or TDS ratios may result in mortgage denial or limit the amount you can borrow. Buyers with strong credit or larger down payments may have more flexibility.
Understanding and managing your debt service ratios is essential to qualify for financing and maintain financial health as a homeowner.
Example of Debt Service Ratios in Action
A buyer with $6,000 monthly income keeps housing costs at $1,800 (30%) and total debt at $2,400 (40%), staying within lender thresholds for GDS and TDS.
Key Takeaways
- GDS and TDS assess mortgage affordability.
- GDS focuses on housing costs; TDS includes all debts.
- Key thresholds: GDS ≤ 32%, TDS ≤ 40–44%.
- Helps ensure borrowers don’t overextend.
- Crucial for mortgage approval and financial planning.
Related Terms
- Mortgage Qualification
- GDS
- TDS
- Affordability
- Budgeting
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Property details for 6525 Mississauga Road. (RBC Capital Markets & CBRE)
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